crutches. Does anyone have any suggestions on managing the logistics of an
active 2 1/2 yr old, a carseat, and the various carryons, plus an adult on
crutches?

Depending on your stroller you either strap the car seat into the
stroller and your child into that car seat, or strap the child into
the stroller and strap the car seat hanging off the back of the
stroller. Both adults use a backpack for your carryon. This works
well with crutches. If it doesn't work to strap the car seat to the
stroller, hang it upside down from the top of your backpack. If you
don't have a ride to the airport, drop off DH and luggage, then go
park. If you can't do a curbside checkin, strap all your checked
luggage to your luggage carrier. While pushing the stroller forward,
pull the luggage along behind you with one hand. Plan extra time for
going up and down curbs. Order wheelchairs for your transfers. I've
also found a leash useful to keep from loosing kids at the airport.

I've flown alone with 2 kids in carseats and managed tight transfers
rushing kids and carseats from one plane to another. Once you get the
logistics down, it does become practical.

--Betsy